A Single-Phase Full-Color Ca₄Si₂O₇F₂:Ce³⁺, Tb³⁺, Sm³⁺ Micron Belt Mat for White-Light Emitting Diode Application

Abstract:

A new kind of Ca₄Si₂O₇F₂:Ce³⁺, Tb³⁺, Sm³⁺ oxyfluoride phosphor micron belt mat was obatained by simply electrospinning process and subsequent heat treatment. XRD result shows that a pure Ca₄Si₂O₇F₂ phase can be obtained at low temperature of around 900 °C. The micron belt precursor has a smooth surface and uniform morphology, and the width and thickness of the belt is about 2 μm and 200 nm. The morphology of micron belt is well retained after heat treatment, forming a plat phosphor mat consisting of uniform micron belt network. Ca₄Si₂O₇F₂:Ce³⁺, Ca₄Si₂O₇F₂:Tb³⁺, and Ca₄Si₂O₇F₂:Sm³⁺ exhibit the characteristic emissions of Ce³⁺ (4f⁷→4f⁶5d¹, blue), Tb³⁺ (4f⁸→4f⁷5d, green), and Sm³⁺ (4f⁶→4f⁶5d, red) under the excitation of near-UV light, respectively. By adjusting the doping concentration of Ce³⁺, Tb³⁺, Sm³⁺ ions a white emission in a single phase was obtained under the excitation of 360 nm. We have demonstrated that Ca₄Si₂O₇F₂:Ce³⁺, Tb³⁺, Sm³⁺ phosphor mat can be a promising candidate for a color-tunable phosphor mat applied in a near-UV White light emitting diodes.

• Periodical: Key Engineering Materials (Volume 697)
• Pages: 727-732
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.697.727
• Online since: July 2016
• Authors: Bo Cui, Qing Hong Zhang, Hong Zhi Wang*, Yao Gang Li
• Keywords: Electrospinning, Micron Belt Mat, Oxyfluoride, White-Lighe Emitting

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